CLI welcome at connection

firmware/src/cli.c

@@ -56,11 +56,12 @@ int cli_match_prefix(const char *str[], int num, const char *prefix)
     return match;
 }
 
+const char *built_time = __DATE__ " " __TIME__;
 static void handle_help(int argc, char *argv[])
 {
     printf("%s", cli_logo);
     printf("\tSN: %016llx\n", board_id_64());
-    printf("\tBuilt: %s %s\n\n", __DATE__, __TIME__);
+    printf("\tBuilt: %s\n\n", built_time);
     printf("Available commands:\n");
     for (int i = 0; i < num_commands; i++) {
         printf("%*s: %s\n", max_cmd_len + 2, commands[i], helps[i]);
@@ -146,10 +147,33 @@ static void process_cmd()
 
 void cli_run()
 {
+    static bool was_connected = false;
+    static uint64_t connect_time = 0;
+    static bool welcomed = false;
+    bool connected = stdio_usb_connected();
+    bool just_connected = connected && !was_connected;
+    was_connected = connected;
+    if (!connected) {
+        return;
+    }
+    if (just_connected) {
+        connect_time = time_us_64();
+        welcomed = false;
+        return;
+    }
+    if (!welcomed && (time_us_64() - connect_time > 200000)) {
+        welcomed = true;
+        cmd_len = 0;
+        handle_help(0, NULL);
+        printf("\n%s", cli_prompt);
+    }
     int c = getchar_timeout_us(0);
     if (c == EOF) {
         return;
     }
+    if (c == 0) {
+        return;
+    }
 
     if (c == '\b' || c == 127) { // both backspace and delete
         if (cmd_len > 0) {

firmware/src/cli.h

@@ -1,20 +1,21 @@
-/*
- * Chu Controller Command Line Framework
- * WHowe <github.com/whowechina>
- */
-
-#ifndef CLI_H
-#define CLI_H
-
-
-typedef void (*cmd_handler_t)(int argc, char *argv[]);
-
-void cli_init(const char *prompt, const char *logo);
-void cli_register(const char *cmd, cmd_handler_t handler, const char *help);
-void cli_run();
-void cli_fps_count(int core);
-
-int cli_extract_non_neg_int(const char *param, int len);
-int cli_match_prefix(const char *str[], int num, const char *prefix);
-
-#endif
+/*
+ * Chu Controller Command Line Framework
+ * WHowe <github.com/whowechina>
+ */
+
+#ifndef CLI_H
+#define CLI_H
+
+
+typedef void (*cmd_handler_t)(int argc, char *argv[]);
+
+void cli_init(const char *prompt, const char *logo);
+void cli_register(const char *cmd, cmd_handler_t handler, const char *help);
+void cli_run();
+void cli_fps_count(int core);
+
+int cli_extract_non_neg_int(const char *param, int len);
+int cli_match_prefix(const char *str[], int num, const char *prefix);
+
+extern const char *built_time;
+#endif